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Sept. 29, 1931. R. s. HUNTER ILLUMINATION CONTROL SYSTEI Filed June 19. 1929 ZShuts-Sheet 1 ATTORNEY P 31- R. B. HUNTER Q 1,825,315

ILLUMINATION CONTROL SYSTBI Filed June 19, 1929 2 Shoots-Sheet 2 v INVENTOR. I

A TTORNEY Patented Sept. 29, 1931 UNITED STATES PATENT OFFICE RICHARD B. HUNTER, OF MILWAUKEE, WISCONSIN, ASSIGNOB- T CUTLEBrHAMMER, INC., 01 MILWAUKEE, WISCONSIN, A CORPORATION OF DELAWARE ILLUMINATION CONTROL SYSTEM Application filed June 19, 1929. Serial No. 372,036.

This invention relates to improvements in illumination control systems.

An object of the inventionis to provide mechanical presetting and Operating means for a multiplicity of dimmer rheostats whereby the illumination intensities of a multiplicity of lamp circuits may be simi1l taneously changed from any values to any other desired values, respectively, the amount of change in any circuit or group of circuits being independent of the change in every other circuit or group of circuits, and the respective rates of change being at all times proportional to the rate of movement of a singleactuating element.

Another object is to provide simple and reliable mechanical means for accomplishmeint of the aforementioned desirable resu ts.

Another object is to provide a manually operable mechanical control system ofthe aforementioned character which is extremely flexible in operation and in the various possible adjustments thereof whereby a practically unlimited number of illumination control combinations may be obtained.

Another and more specific object is to pro vide novel manually operable means for preselecting the changes in illumination inten sity effects to be imposed upon a plurality of groups of lamp circuits and for simultaneously effecting such changes in a proportional manner.

Another object is to provide novel indicating means to facilitate adjustment of the several parts of the device for the purposes aforementioned.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate an embodiment of the invention which will now be described, it being understood that various changes-may be made in the details of construction and operation of the device herein described without departing from the scope of the appended claims.

In the drawings, Figure 1 is a front elevational view of-a portion of a control device constructed in accordance with my invention.

Fig. 2 is a rear elevational view of the elements shown in Fig. 1.

Fig. 3 is a side elevational view of the device illustrated in Figs. 1 and 2, showing the parts in one position of relative adjustment.

Fig. 4 is a similar view showing the parts in another adjusted position.

Fig. 5 is a similar view showing the parts in still another adjusted position.

Fig. 6 is a fragmentary top plan view of certain of the pre-setting and operating elements of the device.

Fig. 7 is a fragmentary elevational view, partly in vertical section, of other elements of the device, and

Fig. 8 is a perspective view of an illumination control system constructed in accordance with my invention, certain of the duplicate elements of the system being shown diagrammatically in dotted lines.

Referring first to Fig. 8, the numeral 15 designates a multiplicity of dimmer rheostats of a well known type, each of said rheostats preferably comprising a base or plate 15* in which the resistance element is embedded and having a multiplicity of contact elements or buttons 15" to be engaged by an oscillatable contactor 15. Each contactor 15 is provided with a pinion 15 to be enga ed by a rack bar 15, a pivoted yoke or bracl mt 15 being provided to maintain the rack bar in driving engagement with the pinion. The rheostats 15 are preferably arranged in groups, and although in Fig. I have illustrated but one group or a portion of one group, it is to be understood that I contemplate the use in each group of a number of rheostats corresponding to the number of circuits of lamps of a given color the intensity of illumination of which is to be controlled, and that a number of groups preferably corresponding to the number. of differently colored lamps of the respective circuits will be employed.

Accordingly I provide a color master shaft 16 having a driving connection with each rack bar 15 of one group of rheostats, said driving connections preferably comprising yokes or brackets 15 secured to and its extreme positions to the other.

movable with the master shaft 16' and each having one end of a rack bar 15 pivoted thereto eccentrically of the master shaft. As will be understood, the color master shaft 16 is oscillatable through a range such as to cause corresponding oscillatory movemert of each contactor of the associated group of rheostats through .a range of approximately 180 degrees upon movement of the color master shaft from each extreme position tothe other. Thus assuming corresponding angular positioning of each yoke 15 upon the color master shaft 16'each of the contactors of the associated group of rheostats will be moved at the same rate and through out equalranges upon movement of the color master shaft.

However, it may be desired to have the individual rheostatcontactors arranged in different angular positions with respect to each other, and accordingly I provide each yoke 15 with means comprising a latch lever 15 whereby the-former may be adjusted to and locked in any desired angular position with respect to the color master lever. Such individual rheostatadjusting and operating means may be of well known form, whereas such means providing for individual adjustment of the respective rheostats of a group might be omitted if desired.

Similarly, it will be apparent that by simply removing and reversing an individual rack bar with respect to its point of engagev ment with the pinion, the direction of oscillation of its associated contactor 15 may be reversed with respect to the direction of oscillation of the color master shaft. In other words, by the means-just described any number of the contactors of the individual rheostats of -a group may be caused to move in one direction or the other during movement of the color master shaft in either direction, whereby the illumination intensity of certain lamp circuits of a group may be increased while the illumination intensity of other lamp circuits of the same group is being decreased.

As aforeindicated I preferably provide a color master shaft 16, 16, etc., for each group of rheostats for controlling the illumination intensity of lamps of-a given color, and I likewise provide common operating means for all of the color master shafts. Said common operating means as shown comprises a grand master shaft 17 which is oscillatable back and forth through a predetermined range, said grand master shaft having an adjustable driving connection with each of the color master shafts whereby each of the latter is'movable from any point to any other predetermined point in its range of movement upon movement of said grand master shaft from either of Grand master shaft 17 is shown as provided with a manual control lever 18 keyed or otherwiserigidly secured thereto, said lever 18 having a hand grip 18 or the like to facilitate manipulation thereof. It is to be understood, however, that any other suitable manual operating means, such as a hand wheel and gearing, might be substituted for the lever 18. A

The operative connection between the grand master shaft 17 and each of the color master shafts 16 will now be described with particular reference to Figs. 1 to 7 of the rigidly secured to the grand master lever 17, as by means of a key 20 or the like, one end of each of a pair of links 21 and 22 being pivotally connected to the free end of lever 19, as by means of a clevis or pivot pin 23 which is retained in place by a cotter pin 24 (Fig. 2). A pivot pin 25 penetrates 'a-lined openings in the other end of the respective links 21 and 22 (Fig.2), said pin 25 forming a' support for a cylindrical roller or wheel 26. Interposed between the opposite ends of roller 26 and the respective links 21 and 22 are the perforated arms 27 and 28 of an adjustable yoke member 29, whereby said yoke member 29 is likewise pivotally engaged with the pin 25, as best shown in Fig. 7. Pin 25 may be held in position by means of a cotter pin 30.

The adjustable yoke 29 includes an internally threaded bushing or neck 31 adapted to receive the threaded en l of a rod 32,a lock-nut 33 being preferably provided for securing said elements in adjusted position. It is to be understood that the elements just described are intended to provide for an initial 'or factory adjustment to compensate for possible inaccuracies in the construction of any of the various parts of the device,

an integral yoke portion 34,. the arms 35 and 36 (Fig. 6) of said yoke portion being adapted to straddle the free end 37 of a curved and relatively short lever 38 which is keyed or otherwise rigidly secured to the color master shaft 16, as indicated in dotted lines at 39; said yoke 34 and lever 38 being pivotally connected, as by means of a pin 40 which is retained in position by a cotter pin 41.

To transmit motion from the grand master shaft 17 to the color master shaft 16, and to vary the proportional rate of movement of the latter with respect to the rate ninety degrees (as shown in dotted lines)' of movement of the former, I provide an adjustable member 42 having an elongated arcuate cam slot 43 the walls of which form a guide bearing for the roller 26. The up per end of member 42 is provided with a pa1r of oppositely arranged parallel arms 44 and 45, each of which is provided with .a perforation which is preferably substantlally concentric with the upper end of the slot 43.

Straddling the arms 44 and 45 and pivotally connected therewith, as by means of pivot pins 46 and 47 is an inverted yoke shaped member 48, the downwardly extendmg perforated arms 49 and50 of the latter being pivotally supported, as by means of shoulder bolts 51 and 52 which are secured by nuts 53 and 54 to the rearward extensions 55 and 56 of brackets 57 and 58. Brackets 57 and 58 are secured by means of bolts 59 or the like to a frame piece 60, as illustrated in Fig. 8, or to a suitable panel shown in dotted lines at 61 in Figs. 3 to 5. Brackets 57 and 58 are each further provided with integral forwardly ex tending portions 62 and 63 forming spaced bearings for the color master shaft 16, and integral segmental portions 64 and 65 hav- 1ng flanges 66 and 67 slightly ofl'set toward each other and arranged concentric to the shaft 16.

The flanges 66 and 67 are provided with a multiplicity of o enings 68 and 69 to rece1 ve a latch pin 0 carried by each of a pair of manually operable levers 71 and 72, said levers being respectively provided with hub portions 73 and 74 which are rotatably mounted uponthe color master shaft 16 on opposite sides of the lever 38.

As best shown in Fig. 3, each of the levers 71 and 72 is of hollow or tubular form to accommodate the full length of the pin which terminates in a rotatable handle or grip 75 rigidly connected thereto. The pin 70 is provided with a fixed washer 76 or the like against which one end of a compression spring 77 is adapted to abut, the other end of said spring being adapted to engage a washer 78 which is slidable upon said pm. Washer 78 is in turn adapted to abut an internal annular flange or projection 79 within the respective lever 71 where by the pin 70 is normally biased inwardly into one of the openings 68 in the flange 66 whereby the lever 71 is locked against movement with respect to segment 64.

The outer end of lever 71 is provided with a cam surface 80 and the pin 70 is provided with a cross pin or projection 81 whereby in the full line position illustrated the pin 7 O is free to engage one of the openings 68in flange 66. However, u on rotation or twisting of handle 75 in eit er direction through an angle of approximately the cross pin 81 rides up the cam surface 80 to its dotted line position,-thus withdrawing the pin 70 from engagement with the flange 66 to permit movement of lever 71 to any desired angular position with re speet to segment 64.

Obviously, when the desired positioning of handle 71 has been effected the same may be latched therein by rotating handle 75 to its full line position for permitting the spring biased movement of pin 70. It will be understood that the construction and operation of lever 72 is substantially like that oflever 71, except that lever 71 is adapted for right-hand mounting and lever 72 is adapted for left-hand mounting.

Lever 71 is further provided at the inner end thereof with a perforated lug .or projection 82 which extends downwardly at substantially aright angle with respect thereto, said lug having pivotally connected thereto one end of a link 83, as by means of a pivot pin 84. Pivot pin 84 may be retained in position by means of a cotter pin 85 (Fig. 6). The other end of link 83 is pivotally connected to a yoke 86 at a point substantially concentric with the lower end of cam slot 43 in member 42, as by means of a pivot pin 87, said pin 87 being likewise retained in position by a cotter pin or the like, not shown. The yoke 87 is preferably supported by and integral with a rod or shank 88, the outer end 89 of which is adapted for threaded engagement with the interior of a bushing 90, which is formed integrally with the member 42 upon a rearwardly extending arm 91 of the latter.

Thus upon movement of the lever 71 to its upper extreme position (as shown in Fig. 3) the lower end of member 42 is drawn to and held in its inner extreme position by the link 83; Whereas upon movement of lever 71 to its lower extreme position (as shown in Figs. 4 and 5) the lower end of member 42 is moved to and held in its outer extreme position. Similarly it will be apparent that the lower end of member 42 may be moved to and held -in any other desired position between the two extreme positions just mentioned by merely adjusting or varying the angular position of lever 71.

Extending upwardly from lever 72 at substantially right angles thereto is a perforated lug or projection 92 to which one end of a link 93 is pivotally connected, as by means of a pivot pin 94; a cotter pin 95 or the like being employed to retain the-latter in position. The other end of link 93 is pivotally engaged with the pivot pin 47 aforementioned; a cotter pin '96 being provided to retain the latter in position. Thus upon movement of lever 72 to its upper extreme position as shown in Figs. 1, 2 and 4 and as indicated in Fig. 3 by the relative position of lug 92 (lever 72 being located directly back of lever 71 in this view of the device), the upper end of member 42 will be moved to and held in its outer extreme position: whereas upon movement of lever 72 to itslower extreme position, as indicated in Fig. 5, the upper end of member 42 will be drawn to and held in its inner extreme position. Similarly, the upper end of member 42 may be caused to assume any other position intermediate of the aforementioned extreme positions by merely varying or adjust ing the relatively angular position of the lever 72.

It will be noted that the pivoted yokeshaped member 48 provides a hanger or support for member 42 which permits the latter to assume any of the aforementioned positions under positive control of the respeet'ive levers 71 and 72 while preventing collapse of the pivotally connected elements.

From the foregoing it will be apparent that with lever 72 in its upper extreme posi-' tion whereby the upper end of member 42 is moved to its outer extreme position, and with the grand master lever moved in a countercloclm ise direction to one of its extreme positions wherein the roller 26 is positioned at the upper end of slot 48 in member 42 (all as shown in Fig. 3), the rod 3 will have drawn the color master shaft 16 in a clockwise direction to one of its extreme positions.

Let it be assumed, for purposes of illustration, that the rheostat contactors 15 controlled by color master shaft 16 are all mounted for simultaneous oscillation in the same direction, and further assuming that the extreme positioning of color master shaft 16 as just described will provide for maximum illumination intensity of all lamp circuits under the control of said color master shaft 16. Then if the lever 71 is located at its upperextrcme position, as indicated in Fig. 3, it is apparent that upon clockwise movement of grand master shaft 17 to its opposite extreme position the roller 26 will be caused to move downwardly and inwardly, due to positioning of the lower end of member 42 in its inner extreme position, which results in movement of color master shaft 16 in a counterclockwise direction throughout its entire range, thus providing' for complete dimming or minimum illumination intensity of all circuits controlled by said color master shaft 16.

However, assume that with all parts in the relative positions illustrated in'Fig. 3 the lever 71 is then moved to its lower extreme position as illustrated in Fig. 4. If the grand master shaft 17 is then moved in a clockwise direction to its opposite extreme position there will be substantially no movement whatsoever of the color master shaft 16,due to the fact that the curved cam slot 43 will then be positioned substantially concentrically with respect to the pivot 40 of the rod 32. Moreover, the arrangement is such that the novel result just mentioned is likewise obtained when each of the levers 71 and 72 is in a position midway between its opposite extreme positions, or when the respective levers 71 and 72 are positioned equal distances on opposite sides of their common middle position. This feature is important in a device of this character since it enables the operator to maintain constant the illumination intensities of certain desired groups of lamp circuits while the illumination intensities of other groups of lamp circuits are being varied through operation of the grand master shaft. 1

Fig. 5 shows by way of example another positioning of the respective parts wherein the levers 71 and 72 are both in their extreme lower positions, and assuming counterclockwise movement of grand master shaft 17 to the position shown, color master shaft 16 will have'been' moved in a counterclockwise direction to its extreme position providing for complete dimming or minimum illumination intensity of the lamp circuits controlled thereby. Thereafter during movement of grand master shaft 17 in a clockwise direction to its op osite extreme position, color master sha t 16 will be gradually and continuously moved in a clockwise direction to its opposite extreme position whereby maximum illumination intensity of the lamp circuits controlled thereby is provided.

It is to be further noted that with the cam slot 43 in any position other than a position concentric with the pivot 40, the movement of color master shaft 16 will be continuous during movement of the grand master lever from either of its extreme positions to the other, and hence the rate of movement of the color master lever 16 will be at all times directly proportional to the rate of movement of the grand master lever. This feature is likewise important since it provides the so-called proportional dimming effect which is extremely desirable in this art. What has been said as to the relation between the grand master shaft 17 and the color master shaft 16 is likewise intended to define the relation of the former to each of the color master shafts employed in a given installation.

In each instance the grand master shaft 17 is shown as having been moved in a counterclockwise direction to one of its extreme positions, with the result that the lever 72 is rendered effective under these conditions to cause movement of the color master shaft in either direction to any desired point in its range whi1e'"'the grand master shaft 17 remains stationary whereas in the aforementioned position of the grand master shaft 17 the lever 71 may be moved in either direction to any desired point within its range without causing any movement whatsoever of the color master shaft 16. In other words, the lever 71 is then operable to adjust the relative position of the cam member 42- whereby the position to be assumed by the color master shaft 16 upon movement of the grand master shaft 17 in a clockwise direction may be readily and definitely preselected.

After the grand master shaft 17 has been moved in such clockwise direction to its opposite extreme position, the lever71 is automatically rendered effective to cause movement of the color master shaft 16 independently of the grand master shaft; and lever 72 is then rendered efiective to preselect the position to be assumed by the color master shaft 16 upon the next movement of the grand master shaft in a counterclockwise direction to the extreme position thereof as illustrated.

In order to definitely indicate the relative positions of the parts and to .facilitate the adjustments aforedescribed, I- ;.preferably provide a front plate or panel for each pair of levers 71 and 72, said panel having therein a Window or opening 98 back of which an indicating plate 99 is reciprocable.

Plate v99 is rigidly secured in any suitable manner to the right angularly bent end 100 of a member 101 which extends rearwardly and is rigidly secured to a verticall extending member 102. The lower end 0 member 102 is pivotally connected, as by means of pivot pin 103, to the lever 19 intermediate the en s of the latter, and the upper end of said ihember is pivotally connected as by means of pivot pin 104 to a similar lever .19 which is keyed or otherwise rigidly secured to a secondary grand master shaft 17.

Thus the lever 19 may be associated with.

a duplicate set of elements including a color master shaft and a pair of levers corresponding to levers 71 and 72 aforedescribed, said elements being arranged directly above the set of elements shown in full lines in Fig. 8, and a suitable platform or runway (not shown) may be provided to facilitate operation of such colormaster control unit.

With the arrangement just described, upon movement of the grand master shaft in a counterclockwise direction to the extreme position illustrated, the lower portion of.

plate 99 will be brought into register with the opening 98, said portion of the plate having suitable legends applied thereto to shaft. Theupper portion of plate 99 is likewise provided with suitable legends to be brought into register with saidopening 98 upon clockwise movement of the grand master shaft to its opposite extreme po,sition, said legends indicating, as a'forestated, that the functions of levers 71 and 72 will then have been reversed.

The levers 71 and 72 project outwardly through respective openings 105 and 106 in the front plate 97, and said levers are respectively provided with arcuate flange portions 107 and 108 which serve as closures for said openings in all positions of said levers. Said flange portions 107 and 108 are respectively provided with projections or pointers larly spaced but being oppositely arranged with respect to each other. The twoseries.

of numerals aforementioned may preferably 9 be carried by aplate 111 secured to the front plate 97, and also preferably arranged in the form of an arc to follow the arc of movement of the pointers 109 and 110.

Each group of rheostats may be mounted in any suitable manner,and as shown in Fig. 8 by way of example, the mounting may comprise the usual bracket structure 112 which may be attached by suitable bolts 113 or the like to a supporting framework or stand 114. The frame 60 aforementioned may be supported in any suitable manner, as by means of a framework composed to tubular elements 115, 116, etc.

The enlargement of the opposite ends of slot 43 in member 42 (as best shown at 117 in Fig. 7) is primarily for the purpose of facilitating machining of this element.

It will be apparent to those skilled in the art that both levers 71 and 72 of each color master control station may-be-moved simultaneously in the same or in opposite directions irrespective of the relative position of the grand master shaft and irrespective of whether the latter is stationary or in mo-v tion. It will be likewise apparent that the number of color master control stationsv to be subject to control by the grand master shaft is practically unlimited, whereas if necessary or desired-the length of the manual operating lever 18 for the grand master shaft 17 may be increased, or a suitable multiplying leverage system may be associated therewith to facilitate manual operation.

Due to the provision of a secondary master shaft 17 it is obvious that the manual operating lever 18 or a duplicate of the latter may be secured to said shaft 17.

Inasmuch as each additional color master similar in construction and operation to that hereinbefore described in detail it is deemed unnecessary to further describe or illustrate my improved illumination control system.

The grand master shaft 17 may be rotatably supported upon the frame by suitable brackets 118 and 119,suitable collars 120 and 121 being secured in spaced relation upon said shaft, as by means of set screws 122 and 123, to prevent endwise movement of the latter. and 119 and collars 120 and 121 are provided for the secondary grand master shaft 17.

What I claim as new and desire to secure by Letters Patent is:

1. In an illumination control system, in combination, a plurality of groups of dimmer rheostats, common operating means for all of said groups of rheostats, and means common to all rheostats of each group for preselecting the proportional influence of said common operating means upon the same to produce simultaneous regulation by the respective groups of rheostats between any two selected points within their respective ranges, said means including means to reverse the influence of said common operating means upon the respective rheostats individually with respect to each other.

2. In an illumination control system, in combination, a plurality of groups of rheostats for controlling the intensity of energization of the lamp circuits respectively associated therewith, operating means comprising a master shaft for each of said groups of rheostats, a grand master shaft having an operative connection with each of said master shafts, and means for preadjusting the driving connections between the grand master shaft and each of said master shafts to provide for movement of each of the latter from either extreme position to the other or between any two intermediate points in its range upon movement of said grand master shaft from either of its extreme positions to the other, said means comprising a pair of levers associated with each master s aft, the levers of each pair being operablealternatively to effect the preadjustment aforementioned or to effect movement of their respective master shaft independently of the grand master shaft.

3. In an illumination control system, in combination, a plurality of groups of dimmer rheostats for controlling the energization intensities of circuits containing differently colored lamps, a plurality of color master shafts each adapted upon movement thereof to effect joint movement of one group of rheostats controlling a particular color of lamps, a grand master shaft to which said color master shafts may be selectively connected to be driven thereby, said grand master shaft and said color master shafts be- Corresponding brackets 118 I ing oscillatable throughout predetermined ranges, and preadjusting means for each of said color master shafts whereby upon movement of said grand master shafts in either direction throughout its complete range the initial voltage impressed upon the lamps controlled by any group of rheostats may be increased or decreased by any amount throughout the working range of "such rheostats, the rate of change of such therewith, said rheostats being divided into groups in accordance with a distinctive characteristic, such as color, of the lamps controlled thereby, operating means comprising a master shaft for each group of rheostats, a grand master shaft having an operative connection with each of said master shafts, and means for preselecting the degree of movement of each master shaft to be effected upon movement of said grand master shaft from one extreme position to the other, said means comprising a pair of levers associated with each master shaft, each of said levers being respectively operable in one extreme position of said grand master shaft to preselect the range of movement of its associated master shaft upon movement of said grand master shaft and each being also operable in another posi- Y tion of said grand master shaft to effect movement of said master shaft independently of said grand master shaft.

5. Pre-set dimmer control means comprising, in combination, a plurality of dimmer rheostats having oscillatable contacts, said rheostats being arranged in a group, a master shaft having a driving connection with each of said contacts, means for effecting movement of said master shaft, said means comprising a lever pivoted to said master shaft eccentrically of the latter, a member having a cam surface against which the free end of said lever is adapted to bear, a second lever pivotally connected to said first mentioned lever to effect movement of said free end of the latter along said cam surface, and means for varying the angular position of said cam surface whereby the degree of movement of said master shaft inrheostats having oscillatable contacts, said lOl llt

rheostats being arranged in a group, a master shaft having a driving connection with each of said contacts, means for effecting movement of said master shaft, said means comprising a lever pivoted to said'master. shaft eccentrically of the latter, a member having a cam surface against which the free end of saidlever'is adapted to bear, a second lever pivotally connected to said first mentioned lever to effect movement of said free end of the latter along said cam surface, and means for varying the angular po- 7 sition of said cam surface whereby the degree of movement of said master s aft incident to a predetermined degree of movement of said free end of the first mentioned lever may. be preselected, said last mentioned means including means to provide for substantially stationarypositioning of said master shaft at any desired position thereof during movement of said first mentioned lever.

7 Pre-set dimmer control means for a plurality of lamp circuits, comprising, in combination, a plurality of dimmer rheostats having oscillatable contactors, means for effecting operation of said contactors simultaneously, said means comprising a master shaft having a driving connection with each of said contactors, agrand master shaft having a driving connection with said master shaft, said last mentioned driving connection comprising a lever pivotally connected at one end to said master shaft eccentrically of the latter, a lateral projection at the other end of said lever, a memher having a cam slot adapted to receive and guide said projection, and a second lever pivotally connected to said first mentioned lever and to said grand master shaft eccentrically of the latter, whereby movement of said grand master shaftin one direction or the other effects corresponding movement of said projection Within said slot.

8. Pro-set dimmer control means for a plurality of lamp circuits, comprising, in combination, a plurality of dimmer rheostats having oscillatable contactors, means for effecting operation of said contactors simultaneously, said means comprising a master shaft having a driving connection with each of said contactors, a grand master shaft having a driving connection With said master shaft, said last mentioned driving connection comprising a lever pivotally connected at one end to said master shaft eccentrically of the latter,a lateral projection at the other end of said lever, a member having a cam slot adapted to receive and guide said projection, a second lever pivotally connected to said first mentioned lever and to said grand master shaft eccentrically of the latter, whereby movement of said grand master shaft in one direction or the other effects corresponding movement of said projection within said slot, and means for adjusting the cam slot member wherebythe rate'of movement of said master shaft may be varied with respect to the rate of movement of said grand master-shaft.

9. Pre-set dimmer control means for a plurality oflamp circuits, comprising, in combination, a plurality of dimmer rheostats having oscillatable contactors, means for effecting operation of said contactors simultaneously, said means comprising a mas ter shaft having a driving connectlon with each of said contactors, a grand master shaft having a driving connection with said master shaft, said last mentioned driving connection comprising a lever pivotally connected atone end to said master shaft eccentrically of the latter, a lateral projection at the other end of said lever, a member hav- Y ing a cam slot adapted to receive and guide said projection, a second lever pivotally connected to said first mentionedwlever and to said grand master shaft eccentrically of the latter, whereby movement of said grand master shaft in one direction or the other effects corresponding movement of said projection Within said slot, and means for adjusting the cam slot member whereby the proportional rate of movement of said master shaft may be varied with respect to the rate' of .movement of said grand master shaft, said adjusting means comprising a pivoted lever having a linkage connection with said cam slot member to provide for vadjustment of. the angular position of the latter.

10. Pre-set dimmer control means for a plurality of lamp circuits, comprising, in combination, a plurality of dimmer rheostats having oscillatable contactors, means for effecting operation of said contactors simultaneously, said means comprising a master shaft having a driving connection with each of said contactors, a grand master shaft having a driving connection with said master shaft, said last mentioned driving connection comprising a lever pivotally connected at one end to said master shaft eccentrically of the latter, a lateral projection at the other end of said lever, a member having a cam slot adapted to receive and guide said projection, a second lever pivotally connected to said first mentioned lever and to said grand master shaft eccentrically of the latter, whereby movement of said grand master shaft in one direction or the other effects corresponding movement of said projection within said slot, and means for adjusting the cam slot member whereb the rate of movement of said master sha t may be varied with respect to the rate of movement of said grand master shaft, said adjusting means comprising a pair of pivoted levers, each respectively connected to one end of said cam slot member, whereby loo comprising, in combination, a plurality of dimmer rheostats having oscillatable contacts, said rheostats being arranged in a group, an oscillatable master shaft having a driving connection with each of said contacts, an oscillatable grand master shaft having a driving connection with said master shaft, said connection including a lever one end of which is pivotall connected to said master shaft eccentrical y of the latter, a second lever pivotally connected to said first mentioned lever and to said-grand master shaft eccentrically of the latter, sai d first mentioned lever having a lateral projection,

a member having an arcuate slot to receive and guide said projection upon movement thereof incident to movement of said grand master shaft, and means for adjusting the thereby provide for continuous movement of said master shaft from any position to any other desired position within its range coincident with movement of said grand master shaft from either of its extreme positions to the other.

12. Pre-setting dimmer control meansgroup, an oscillatable master shaft having a driving connection with each of said contacts, an oscillatable grand master shaft having a driving connection with said master shaft, said connection including a lever one end of which is pivotally connected to said master shaft eccentrically of the latter, a

' second lever pivotally connected to said first mentioned lever and to said grand master shaft eccentrically of the latter, said first mentioned lever having a lateral projection, a member having an arcuate slot to receive and guide said projection upon movement thereof incident to movement of said grand master shaft, and means for adjusting'the angular position of said arcuate slot to thereby provide for movement of said master shaft from any position to any other desired position within its range upon movement of said grand master shaft from either of its extreme positions 'to the other, said arcuate slot being further adapted upon concentric positioning thereof with respect to the pivotal connection between said first mentioned lever and said master shaft to provide for inaction of the latter upon move-- ter shaft, said connection including a lever one end of which is pivotally connected to ,said master shaft eccentrically of the latter,

a second lever pivotally connected to said first mentioned lever and to said grand master shaft eccentrically of the latter, said first mentioned lever having a lateral projec'tion; a member having an arcuate slot to receive and guide said projection upon movement thereof incident to movement of said grand master shaft, means for adjusting the angular position of said arcuate slot to thereby provide for movement of said master shaft from any position to any other desired position within its range upon movement of said grand master shaft from either of its extreme positions to the other, said means comprising a pair of manually operangular position of said arcuate slot to able levers pivoted concentrically with respect to said master shaft, and a pair of links each pivotally connected respectively to one of said last mentioned levers and to one of the respective ends of said slotted member.

l4. Pre-setting proportional dimmer control means comprising, in combination, a plurality of dimmer rheostats having oscillatable contacts, said rheostats being arran ed in a group, an oscillatable master sha t having a driving connection with each of said contacts, an oscillatable grand master shaft having a driving connection with said master shaft, said connection including a lever one end of which is pivotally connected to said master shaft eccentrically of the latter, a second lever pivotally connected to said first mentioned lever and to said grand master shaft eccentrically of the latter, said first mentioned lever having a lateral projection, a member having an arcuate slot to receive and guide said projection upon movement thereof incident to movement of said grand master shaft, means manually operable levers pivoted concentrically with respect to said master shaft,

and a pair of links each pivotally connected respectively to one of said last mentioned levers and to one of the respective ends of said slotted member, said last mentioned levers being adjustable "independently of each other and each having means for positiviely maintaining the same in adjusted position. v v

15. A pre-set proportional dimmer system comprising, in combination, a multiplicity of dimmer rheostats having oscil- 'latable contacts, said rheostats being arnections between said grand master shaft and each of said master shafts, each of said last mentioned driving connections comprising a member having an arcuate slot, a link pivoted eccentrically to its respective master shaft and having a portion thereof guided by said slot, a second link pivotally connected eccentric-ally to said grand master shaft and to said first mentioned link to thereby provide for movement of its respective master shaft at a rate proportional to the rate of movement of the grand mastershaft, and means for independently varying the angular position of each slotted member whereby the range of movement of each master shaft and the proportional rate of movement thereof with respect to the range and rate of movement of the grand master shaft may be varied individually as desired.

16. A pre-set proportional dimmersystem comprising, in combination, a multiplicity of dimmer rheostats having oscillatable con- --tacts, said rheostats being arranged in groups, an oscillatable master shaft for each group of rheostats, driving connections between each master shaft and the contacts of the group of rheostats controlled thereby, an oscillatable grand master shaft, independently adjustable driving connections between said grand master shaft and each of said master shafts, each of said last mentioned drlvmg connectlons comprising a member having an arcuate slot, a link pivot-.

ed eccentrically to its respective master shaft and having a portion thereof guided by said slot, a second link pivotally connected eccentrically to said grand master shaft and to said first mentioned link to thereby provide y of dimmer rheostats having oscillatable confor movement of its respective master shaft at a rate directly proportional to the rate of movement of the grand master shaft, and means for independently varying the angular position of each slotted member whereby the range of movement of each master shaft and the proportional rate of movement thereof with respect to the range and rate of movement of the grand master shaft may be varied individually as desired, said last mentioned means comprising a pair of manually controlled levers operatively connected with opposite ends of said slotted member and operable alternately to preselect the range of movement of their associated master shaft upon subsequent movement of the 4 grand master shaft from one extreme position to the other, 4

17. A pre-set proportional dimmer system comprising, in combination, a multiplicity of dimmer rheostats having oscillatable contacts, said rheostats being arranged in groups, an oscillatable-master shaft for each group of rheostats, driving connections between each master shaft and the contacts of the group of rheostats controlled thereby, an

oscillatable grand master shaft, in'dependcntly adjustable driving connections between said grand master shaftand each of said master shafts, each of said last mentioned driving connections comprising a' member having an arcuate slot, a link .pivoted eccentrically to its respective master shaft and having a portion thereof guided by said slot, a second link pivotally connected eccentrically to said grand master shaft and to said firstmentioned link to thereby pro-- vide for movementof its respective master shaft at a rate proportional to the rate of movement of the grand master shaft, means for independently varying the angular position of each. slotted member 'vvhereb the range of movement of each mastersha t and the proportional rate of, movement thereof with respect to the range and'rate of movement of the grand master shaft may be varied individually as desired, said last mentioned means comprising a pair of manually controlled levers operatively connected with opposite ends of said slotted member and operable alternately to preselect the range of movement of their associated master shaft upon subsequent movement of the -grand master shaft from one extreme position to the other, and means comprising a dial associated with each of said manually con trolled levers, one of said dials being adapted to indicate the angular'po'sition of its associated master shaft when the grand -master shaft is in one extreme position and the other dial being adapted to indicate a preselected angular position of said master shaft under the conditions aforementioned. 18. A pre-set proportional dimmer system comprising, in combination, a multiplicity tacts, said rheostats being arranged 'in groups, an oscillatable master shaft for each group of rheostats, driving connections between each master shaft and the contacts of the group of rheostats controlled thereby, an oscillatable grand master shaft, independently adjustable driving connections between said grand master shaft and each of said master shafts, each of said last mentioned driving. connections comprising a member having an arcuate slot, a link pivoted eccentrically to its respective master shaft and having a portion thereof guided by said slot, a second link pivotally connected eccentrically to said grand master shaft and to said first mentioned link to thereby provide for movement of its respective master shaft at a rate directly proportional to the rate of movement of the grand master shaft, means for independently varying the angular position of each slotted member whereby the range of move-- ment of each master shaft and the proportional rate of movement thereof with respect to the range and rate of movement of the grand master shaft may be varied individually as desired, said last mentioned means comprising a pair of manually controlled levers operatively connected with opposite ends of said slotted member and operable alternately to preselect the range of movement of their associated master shaft upon subsequent movement of the grand master shaft from one extreme position to the other, and means comprising a dial associated with each of said manually controlled levers, one of said dials being adapted to indicate the angular position of its asso-. ciated master shaft when the grand master shaft is in one extreme position and the other dial being adapted to indicate a preselected angular position of said master shaft under the conditions aforementioned, each of said dials being adapted to perform the aforementioned indicating functions of the other when the grand master shaft is in its opposite extreme position.

19. A pre-set proportional dimmer system comprising, in combination, a multiplicity of dimmer rheostats having oscillatable contacts, said rheostats being arranged in groups, an oscillatable master shaft for each group of rheostats, driving connections between each master shaft and the contacts of the group of rheostats controlled thereby, an oscillatable grand master shaft, independently adjustable driving connections between said grand master shaft and each of said master shafts, each of said last men member having an arcuate slot, a link pivoted eccentrically to its respective master shaftand having a portion thereof guided by said slot, a second link pivotally con nected eccentrically to said grand master shaft and to said first mentioned link to member and operable alternately to preselect the range of movement of their associated master shaft upon subse uent movement of the grand master sha from one extreme position to the other, means comprising a dial associated with each of said manually controlled levers, one of said dials being adapted to indicate the angular posi tion of its associated master shaft when the grand master shaft is in one extreme position and the other dial being adapted -to indicate a preselected angular position of said master shaft under' the conditions aforementioned, each of said dials being adapted to perform the aforementioned indicating functions of the other when the grand master shaft is in its opposite extreme position, and means operable automatically by 1 said grand master shaft to designate which of the manually controlled levers is available for preselecting the angular position to be assumed by the respective master shaft upon subsequent movement of the grand plaster shaft to its opposite extreme posi- In witness whereof, I have hereunto sub scribed my name.

RICHARD B. HUNTER.

.tioned driving connections comprising a and rate of movement of the grand mastershaft may be varied individually as desired, said last mentioned means comprising a pair of manually controlled levers operatively connected with opposite ends of said slotted 

